Method of constructing footwear having a sealed dead-end chamber



April 17, 1956 C. A. RILEY ET AL METHOD OF CONSTRUCTING FOOTWEAR HAVINGA SEALED DEAD-END CHAMBER Original Filed May 51, 1952 United StatesPatent METHOD OF CONSTRUCTING FOOTWEAR HAV- ING A SEALED DEAD-ENDCHAMBER Chester A. Riley, Melrose, and Harold H. Whittemore,

Wobum, Mass., assignors to The B. F. Goodrich Company, New York, N. Y.,a corporation of New York Original application May 31, 1952, Serial No.290,976. Divided and this application August 6, 1954, Serial No. 448,168

8 Claims. (Cl. 154-418) This invention relates to a method ofconstructing an article of footwear having a sealed dead-air chamberformed between and by the walls thereof and pertains more particularlyto a method of removing air from the dead-air chamber of the footwearduring the vulcanization thereof.

It is, an object of this invention to provide a method of constructingan article of footwear having a dead-air chamber formed between and bythe walls thereof.

It is also an object of this invention to provide a method of bleedingair from a dead-air chamber, formed between and by the walls of anarticle of footwear, during the volcanization of said footwear toprevent inflation of the walls of the article during the vulcanizationprocess caused by the expansion of air confined within the dead-airchamber.

It is a further object of this invention to provide a convenient andeconomical method of constructing insulated footwear.

Other objects of this invention will be apparent from the descriptionand drawings which follow.

In the construction of articles of footwear provided with a sealeddead-air chamber formed between the walls thereof for providinginsulation around the foot and ankle of the wearer to protect theseportions of the body from extreme cold, it has been found desirable toform portions of the walls of the article of rubber or rubber-likematerials which must be vulcanized to impart the desired physicalproperties thereto. If heat is used to vulcanize the rubber orrubber-like materials in the article of footwear, it has been foundnecessary during the vulcanization process to maintain the pressure ofthe air confined in the dead-air chamber substantially the same as theatmospheric pressure to prevent ballooning or inflation of the walls ofthe article caused by the expansion of the air within the dead-airchamber upon being heated. Accordingly, it is necessary to provide anopening into the deadair chamber during the process of vulcanizing theboot or shoe to allow air within the dead-air chamber to escape to theatmosphere as it expands because of being heated. It has been customaryto bleed air from the dead-air chamber during the vulcanization processby puncturing a side wall of the chamber at a zone remote from themargin of the article. This method of bleeding air from the dead-airchamber during the vulcanization of the article has not proven entirelysatisfactory, however, since it is a difficult and tedious operation toreseal the chamber after the completion of the vulcanization process andsince an objectionable unworkmanlike seal results.

We have found a method of making articles of footwear provided with asealed dead-air chamber between the walls of the article which attainsthe objectives set forth above and eliminates the deficiencies ofheretofore known methods of bleeding air from a dead-air chamber in aboot or shoe during the vulcanization thereof by venting air through amarginal zone of the boot or shoe.

For a clearer understanding of this invention, reference will be made,henceforth, to a method of constructing a boot having a sealed dead-airchamber formed between and by the walls thereof; however, it will beunderstood that we do not intend our invention be limited to thisspecific illustration.

In the drawings:

Fig. 1 is a side elevation view partly broken away and in section of aboot embodying this invention;

Fig. 2 is a section on line 2-2 of Fig. 1; and

Fig. 3 is a section on line 3-3 of Fig. l, but showing a modification.

Referring to the drawings, boot 10 comprises a flexible leg-enclosingupper portion 11 extending generally to about mid-calf height, and asole assembly 12. Upper portion 11 is constructed of several layersdisposed one over another to form a laminated assembly and includes acontinuous flexible resilient waterand moisture-impervious outer barrier13 of rubber or rubber-like material reinforced with fabric material 14,a flexible outer insulating member 15, a flexible inner insulatingmember 16, and a continuous flexible resilient waterandmoistureimpervious inner barrier 17 of rubber or rubber-like materialreinforced with fabric material 18.

Outer insulating member 15, which may be constructed of any suitableheat-insulating material, such as deep pile fabric, shearling, rabbithair, spun glass, spun nylon, and the like, is disposed over and adheredto the inner face of barrier 13 and extends upwardly from the region ofsole assembly 12 to any desired height and substantially continuouslyaround the footand ankle-enclosing portion of upper portion 11. Innerinsulating member 16, which may be constructed of the sameheat-insulating material as outer insulating member 15 and which opposesouter insulating member 15 in face-to-face relationship, is disposedover and adhered to the outer face of inner barrier 17 and, like outerinsulating member 15, extends upwardly from the region of sole assembly12 to any desired height, preferably to the same height as outerinsulating member 15, and substantially continuously around the footandankle-enclosing portion of upper portion 11.

Barrier 13 extends over the entire outer face of outer insulating member15 and over the entire sole portion of boot 10; and barrier 17 extendsover the entire inner face of inner insulating member 16 and over theentire sole portion of boot 10. The upper margins of barriers 13 and 17are completely sealed together in the finished boot to provide boot 10with a sealed dead-air chamber formed between and by the walls of boot10, the deadair chamber providing insulation for the foot and ankle ofthe wearer because of the air sealed therein.

In constructing boot 10 in accordance with this invention a hollowtubular member 20 is disposed between the upper margins of barrier 13and barrier 17, before these margins are sealed together, with one ofits open ends 21 extending between insulating members 15 and 16 into thedead-air chamber of boot 10 and with its other open end 22 extending tothe upper edge 23 of boot ltl. Tubular member 20 is desirablyconstructed of a flexible material which is incapable of adhering toitself but which is capable of being adhered with a rubbery cement torubber or rubber-like materials or to fabric or which is capable ofbeing adhered directly to rubber or rubber-like materials by vulcanizingthem together. Preferably member 20 is a flexible braided fabric tubularelement. The upper margins of barriers 13 and 17 are sealed together inface-to-face relationship with tubular member 20 adhered therebetween,as shown in Fig. 3, to form a deadair chamber in boot 10 which iscompletely sealed except for a passageway from the dead-air chamber ofboot 10 to the atmosphere formed by tubular member 20. If it is desired,tubular member 20 may be coated with a rubbery cement prior to beingincorporated betwee' barriers 13 and 17 or may be disposed and adheredbetween strips or layers of rubber or rubber-like material, which may bereinforced with a fabric material, the assembly then being adheredbetween barriers 13 and 17.

After all of the elements of the boo-t have been assembled, boot isvulcanized in the usual manner while still on the last by theapplication of heat. As the air confined in the dead-air chamber of theboot becomes heated, it expands and is automatically vented throughtubular member to the atmosphere to maintain the pressure of the airwithin the dead-air chamber the same as the pressure of the air on theoutside of the boot preventing ballooning or inflation of the walls ofboot 10 which would result if the chamber were completely sealed.

After boot lltl has been vulcanized to the desired degree, it is allowedto cool to room temperature. As the air within the dead-air chamber ofthe boot is cooled, the pressure of the air within the chamber decreasesto a pressure below that of the air surrounding the boot and air fromthe atmosphere enters the dead-air chamber of the boot to establish acondition of equilibrium between the air within the chamber and the airexterior of the boot.

vhen boot iii has cooled preferably to approximately room temperatureand the air within the dead-air chamber of the boot and the airsurrounding the boot are in a condition of equilibrium, tubular member2i) is sealed closed by forcing a sealing material, such as anair-curing rubbery cement or latex, into end 22 of tubular member 2t)and thereafter pressing member 20 together, or by plugging end 22 ofmember 20 with any suitable plug device.

in another embodiment of this invention, as shown in Fig. 3, tubularmember 20 is provided with a relatively flexible supporting member orcore 24 of non-collapsible material, such as a metal wire, whichprevents tubular member 26" from being inadvertently collapsed duringthe assembly of boot iii. After boot 10 has been completely assembledand just before it is vulcanized, core 24 is removed and the boot isvulcanized and member 20 is sealed as described above.

This invention provides a method of venting air from a dead-air chamberformed between the walls of a boot or shoe containing rubber orrubber-like materials during the vulcanization process thereof toprevent ballooning or inflation of the walls of the boot or shoe becauseof the expansion of air within the dead-air chamber as a result of itsbeing heated. Also, this invention allows air to flow into the dead-airchamber of the boot or shoe as the boot or shoe is cooled to roomtemperature after it has been vulcanized.

in bleeding the air from the dead-air chamber through the top margin ofthe boot or shoe during the vulcanization of the boot or shoe, theprocess of puncturing a side wall of the dead-air chamber is eliminatedand, conseqeuntly, provides a boot or shoe of better quality andworkmanship.

Our invention, also, eliminates the tedious and timeconsuming operationof sealing the punctured side wall of the chamber subsequent to thevulcanization of the boot or shoe and provides a more positive seal ofthe deadair chamber than is obtained in sealing a puncture in the sidewall of the chamber.

it is clear that obvious modifications and variations of this inventionmay be made without departing from the spirit and scope of thisinvention as defined in the appended claims.

This application is a division of application Serial No. 290,976 filedMay 31, 1952.

We claim:

1. The method of making an article of footwear having generally parallelopposing wall members comprising vuleanizable rubber-like materialsealed together along their marginal zones to form a hermetically-sealeddeadair chamber therebetween, which method comprises providing a passagebetween opposing faces of said vulcanizable wall members in the marginalzones thereof communicating with said chamber and with the atmosphereand being open for the flow of gas through said passage both out of andinto said chamber, heating said article to vulcanize the rubber portionsof the article and simultaneously discharging gases from said chamber tothe atmosphere through said open passage, cooling said article andsimultaneously vdrawing gases from the atmosphere through said passageinto the chamber, and sealing said passage to stop completely thepassage of gases either out of or into said chamber.

2. The method of making an article of footwear having a pair ofgenerally parallel opposing wall members comprising resilientvulcanizable rubbery material completely sealed together along theirmarginal zones to form a hermetically-sealed dead-air chambertherebetween, which method comprises providing a hollow open-endedtubular member between the opposing faces of said vulcanizable wallmembers in the marginal zones thereof communicating with said chamberand with the atmosphere, said tubular member being open for the flow ofgas both into and out of said chamber, heating said article to vulcanizeit and simultaneously discharging gases from said chamber to theatmosphere through said tubular member, cooling said article toapproximately room temperature and simultaneously passing air from theatmosphere through said tubular member into the chamber, and sealingsaid tubular member closed to stop completely the flow of gases eitherout of or into the chamber.

3. The method of making an article of footwear having a pair ofgenerally parallel opposing walls comprising a resilient vulcanizablerubbery material and having a sealed dead-air chamber formed between andby the walls thereof by completely sealing the margins of said wallstogether, said method comprising providing a tubular member between theopposing faces of said margins of said vulcanizable Walls with one ofits ends extending intosaid dead-air chamber and with its other endcommunicating with the atmosphere, sealing said margins of said wallstogether with said tubular member adherently sealed therebetween, saidtubular member being open for the tlow of gases both out of and intosaid chamber, heating said article to vulcanize it and simultaneouslydischarging gases from the chamber through said tubular member to theatmosphere, cooling said article to approximately room temperature andsimultaneously drawing air from the atmosphere through said tubularmember into the chamber, and sealing said tubular member closed to stopcompletely the passage of gases out of or into said chamber.

4. The method of making an article of footwear having a pair ofgenerally parallel opposing walls comprising a resilient vulcanizablerubbery material and having a sealed dead-air chamber formed between andby the walls thereof by completely sealing the margins of said wallstogether, said method comprising providing a hollow openended tubularmember between the opposing faces of the upper margins of saidvulcanizable walls with one of its open ends extending into said deadairchamber and with its other open end communicating with the atmosphere,sealing said margins of said walls together with said tubular memberadherently sealed therebetween, said tubular member being open to permita free flow of fluids both into and out of the said chamber, heatingsaid article to vulcanize it and simultaneously discharging gases fromthe chamber through the tubular member into the atmosphere, cooling saidarticle to approximately room tem perature and simultaneously admittingatmospheric air through said tubular member into the chamber, andsealing said tubular member closed to stop completely the passage offluids either out of or into said chamber.

5. The method of making an article of footwear having a pair ofgenerally parallel opposing walls comprising a resilient vulcanizablerubbery material and having a sealed dead-air chamber formed between andby the walls thereof by completely sealing the margins of said wallstogether,

said method comprising providing a hollow open-ended tubular memberbetween the opposing faces of the upper margins of said vulcanizablewalls with one of its open ends extending into said dead-air chamber andwith its other open end communicating with the atmosphere, sealing saidmargins of said walls together with said tubular member adherentlysealed therebetween, heating said article to vulcanize the rubberportions of the article while venting gases from said chamber to theatmosphere through said tubular member, cooling said article toapproximately room temperature while admitting atmospheric air throughsaid tubular member into said chamber, and sealing said tubular memberclosed by disposing a rubbery sealing material in the tubular openingthereof to stop completely the flow of fluids through said tubularmember.

6. The method of making an article of footwear having a pair ofgenerally parallel opposing walls comprising a resilient vulcanizablerubbery material and having a sealed dead-air chamber formed between andby opposing walls thereof by completely sealing the margins of saidwalls together, said method comprising providing a flexible hollowopen-ended fabric tubular member between opposing faces of said marginsof said vulcanizable walls with one of its open ends extending into saiddead-air chamber and with its other open end communicating withtheatmosphere, sealing said opposing faces of said margins of said wallstogether with said tubular member adherently sealed therebetween,heating said article to vulcanize the rubber portions thereof whileventing gases from said chamber to the atmosphere through said tubularmember, cooling said article to approximately room temperature whileadmitting atmospheric air through said tubular member into said chamber,and sealing said tubular member together to stop completely the flow offluids into said chamber.

7. The method of making an article of footwear having a pair ofgenerally parallel opposing Walls comprising a resilient vulcanizablerubbery material and having a sealed dead-air chamber formed between andby opposing walls thereof-by completely sealing the margins of saidwalls to gether, said method comprising providing a tubular memherhaving a readily removable internal supporting member between theopposing faces of the upper margins of said vulcanizable walls with oneof its ends extending into said dead-air chamber and with its other endcommunicating with the atmosphere, sealing said opposing faces of saidmargins of said walls together with said tubular member adherentlysealed therebctween, removing said supporting member from said tubularmember to provide an open passageway for fluids between the chamber andthe atmosphere, heating said article to vulcanize the rubber portionsthereof while venting gases from the chamber through said tubular memberto the atmosphere, cooling said article to approximately roomtemperature while admitting atmospheric air through said tubular memberinto said chamber, and sealing the opening of said tubular member closedto prevent completely the flow of fluids through said tubular member.

8. The method of making an article of footwear having a pairof generallyparallel opposing Walls comprising a resilient vulcanizable rubberymaterial and having a sealed dead-air chamber formed between and byopposing walls thereof by completely sealing the margins of said wallstogether, said method comprising providing a flexible fabric tubularmember having a readily removable internal supporting member between theopposing faces of the upper margins of said vulcanizable walls with oneof its ends extending into said dead-air chamber and with its other endcommunicating with the atmosphere, sealing said opposing faces of saidmargins of said walls together with said tubular member adherentlysealed therebetween, removing said supporting member from said fabrictubular member to provide an open passageway for fluids between the saidchamber and the atmosphere, heating said article to vulcanize the rubberportions thereof While venting gases from the chamber through saidtubular member to the atmosphere, cooling said article to roomtemperature while admitting atmospheric air through said tubular memberinto said chamber, and sealing opposing walls of said fabric tubularmember together to prevent completely the flow of fluids through said!tubular member.

References Cited in the file of this patent UNITED STATES PATENTS

1. THE METHOD OF MAKING AN ARTICLE OF FOOTWEAR HAVING GENERALLY PARALLELOPPOSING WALL MEMBERS COMPRISING VULCANIZABLE RUBBER-LIKE MATERIALSEALED TOGETHER ALONG THEIR MARGINAL ZONES TO FORM A HERMETICALLY-SEALEDDEADAIR CHAMBER THEREBETWEEN, WHICH METHOD COMPRISES PROVIDING A PASSAGEBETWEEN OPPOSING FACES OF SAID VULCANIZABLE WALL MEMBERS IN THE MARGINALZONES THEREOF COMMUNICATING WITH SAID CHAMBER AND WITH THE ATMOSPHEREAND BEING OPEN FOR THE FLOW OF GAS THROUGH SAID PASSAGE BOTH OUT OF ANDINTO SAID CHAMBER, HEATING SAID ARTICLE TO VULCANIZE THE RUBBER PORTIONSOF THE ARTICLE AND SIMULTANEOUSLY DISCHARGING GASES FROM SAID CHAMBER TOTHE ATMOSPHERE THROUGH SAID OPEN PASSAGE, COOLING SAID ARTICLE ANDSIMULTANEOUSLY DRAWING GASES FROM THE ATMOSPHERE THROUGH SAID PASSAGEINTO THE CHAMBER, AND SEALING SAID PASSAGE TO STOP COMPLETELY THEPASSAGE OF GASES EITHER OUT OF OR INTO SAID CHAMBER.